Inflatable Jacquard-Woven Textiles for Structural Applications

ABSTRACT

Embodiments of the invention comprise woven multilayer textiles having shaped, enclosed, inflatable pockets, where the inflated textile carries tension, compression, torsion and/or bending loads. Composite structures incorporating such inflatable members or spars are also described and claimed.

CONTINUITY AND CLAIM OF PRIORITY

This is an original U.S. patent application.

FIELD

The invention relates to structurally defined components formed from specially-shaped woven fabrics. More specifically, the invention relates to inflatable textile shapes woven as a variable number of plies, said shapes including some woven (rather than sewn or welded) seams.

BACKGROUND

The simplest woven fabrics comprise two roughly-perpendicular sets of threads: the warp and the weft (see FIG. 3). The warp threads 310 extend the length of the fabric, while the weft threads 320 cross from side to side. Each weft thread passes over one warp thread, then under the next, and so on as it travels across the fabric. The next adjacent weft thread passes under the first warp thread, then over the next, generally in an inverted pattern compared to the adjacent weft thread.

Decorative patterns can be woven by changing weft-thread colors and/or by altering the over/under pattern in one direction or another, so that (for example) a weft thread might pass over two adjacent warp threads, then under the next two, and so on; or two successive weft threads might use the same over/under pattern, rather than the typical inverted pattern. FIG. 4 shows several swatches of fabric woven as described here: a first swatch 410 is simple staggered over-3/under-1 warp and weft (this is a common pattern recognizable as “blue jeans” denim), while a second swatch 420 shows a checkerboard pattern woven with over/under 3, and a third swatch 430 shows how an alphanumeric character pattern can be woven.

Jacquard looms (named for inventor Joseph Marie JACQUARD) can be configured to create particular over/under weaving patterns under mechanical or electronic control, thus automatically producing complicated designs. Modern Jacquard looms offer sophisticated control of both warp and weft threads, which permits textile designers to specify and manufacture fabrics with both structural and aesthetic (design) characteristics.

SUMMARY

Embodiments of the invention include a woven textile featuring a shaped, enclosed pocket or chamber (or a multicell area) that can be inflated to form a structure (or a component of a structure) that can withstand multi-modal loading.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a fabric swatch having three lengthwise woven channels according to an embodiment of the invention.

FIG. 2 shows a cross-section of a woven structure having a complex system of adjacent channels woven into it.

FIG. 3 shows a detail of a prior-art woven textile, illustrating the simplest over/under weaving pattern.

FIG. 4 shows several prior-art woven textile swatches, where variations of weaving pattern have been used to create designs visible on the surface of a single-layer fabric.

FIG. 5 shows a shaped pocket woven into a textile according to an embodiment of the invention.

FIG. 6 illustrates a limitation on the structures that can be woven successfully.

FIGS. 7A and 7B show how an inflated structure and its corresponding woven structure may be related.

FIG. 8 shows an air mattress constructed according to an embodiment.

FIG. 9 shows a variant internal structure for an air mattress according to an embodiment.

FIG. 10 shows a stand-up paddleboard woven according to an embodiment.

FIG. 11 shows several possible cell structures for the stand-up paddleboard. Similar structures are also compatible for mattresses.

FIG. 12 shows how several structures may be woven together, then cut apart, assembled and inflated to form a sofa.

FIG. 13 shows how inflatable spars according to an embodiment may be incorporated into a chair.

FIG. 14 shows how inflatable spars may be shaped and assembled into a sunshade/tent structure.

FIG. 15 shows how inflatable spars according to an embodiment may be used to support a camping tent.

FIGS. 16A and 16B shows how inflatable spars according to an embodiment may be used as a support frame for a crib or playpen.

FIG. 17 shows how several inflatable substructures according to an embodiment may be laid out on a length of woven fabric. FIG. 18 shows how these structures may be arranged and assembled to form a support structure for a kite-surfing wing.

DETAILED DESCRIPTION

Embodiments of the invention use Jacquard weaving techniques to construct textiles having partially- or completely-enclosed pockets that can withstand a fluid or gaseous pressure differential (i.e., they can be filled or inflated). The pockets have fewer or no sewn seams, compared to an inflatable or fillable pocket constructed by prior-art methods (principally needle-and-thread sewing and welding). Sewing can damage fabric by poking holes in it, and the threads with which a pocket is sewn concentrate stresses on the seam. Thus, by comparison to prior-art methods, textiles according to embodiments of the invention are stronger and can withstand greater pressures. These characteristics permit the fabrication of new structural members having superior strength-to-weight ratios and other beneficial, distinguishing features.

FIG. 1 shows a portion of a fabric swatch woven according to an embodiment of the invention. The warp threads (seen end-on as black clots at, e.g., 110) run the length of the fabric, and the sides of the fabric (the first and last few warp threads) are woven with weft threads 120 (in white) in a simple pattern to form the selvage—an edge that resists fraying or unraveling.

The lengthwise (warpwise) ridges or pockets 130 are formed, not by sewing or welding seams clown the length of two separate layers of fabric (as one might do according to the prior art), but by selectively weaving together subsets of the warp and weft threads. At the selvage and at the pinched portions of the fabric, all warp and weft threads are woven together. (These portions are depicted in crosshatch, e.g. at 140 and 150.) At points between these locations, half of the warp and half of the weft threads are woven together to form the upper surface, and the other half of the warp and weft threads are woven together to form the lower surface.

FIG. 2 shows a cross-section through a more-complicated woven fabric. This view looks end-on clown the warp threads, and the weft threads travel generally horizontally across the figure. Any individual weft thread passes in a standard over/under pattern across its warp threads, but it may pass across only outer-surface warp threads, only inner-structure warp threads, or may pass across some outer and some inner warp threads. The overall result is the formation of a group of adjacent lozenge or honeycomb shaped channels that pass clown the length of the fabric. Some of the channels may share at least portions of their interior walls.

Even more complicated internal structures may be woven in this way, subject to the limitation that the length of each weft thread must be substantially the same. Another way of expressing this limitation that the woven structure is must be capable of being pulled flat and taut from edge to edge on the loom. It is appreciated that portions of the fabric where only a fraction of the warp and weft threads are woven together are less-densely covered than portions where more threads are woven together.

FIGS. 1 and 2 introduce the method used by embodiments of the invention to form multiple warpwise channels along a bolt of fabric woven in a single operation by a Jacquard loom. However, note that a Jacquard loom can also form weftwise channels across the width of the fabric by changing the weaving pattern along the warp threads. Pockets of arbitrary shape and orientation can be formed by changing the weaving pattern along both directions. For example, the banana-shaped pocket 510 shown in FIG. 5 can be formed in a single weaving operation by changing the warp and weft over/under pattern in both directions as weaving progresses. Pocket 510 is shown partially cut away and partially inflated, but it should be understood that a completely-enclosed pocket can also be formed this way.

The border of the pocket, gray crosshatch at 520 (also described at times as the boundary, the perimeter, the peripheral edge or the seam allowance) usually consists of all warp and weft threads woven together in a very dense, simple, alternating over/under pattern. The fabric in this area is a single layer thick, and the shaped pocket may be cut from the bulk woven cloth here.

It is appreciated that the selvedge of woven cloth is often formed by turning a weft thread around the outside warp thread and returning it back towards the other side. Such a selvedge resists fraying because the turned-back weft thread locks the outside warp thread. (See FIG. 3 at 330.)

However, when a woven, shaped pocket structure according to an embodiment is cut in its seam-allowance area, the edges of the seam allowance may be less resistant to fraying. To prevent fraying here, techniques such as sewing, edge binding, or heat treatment (e.g., melting exposed threads together) may be useful. Note that this area of the pocket is inherently strong, because it includes all warp and weft threads woven together. Thus, in addition to being somewhat resistant to fraying on its own, it also offers a favorable place to attach other elements of a composite structure, as described below.

Multi-layer and multi-chamber structures with arbitrary outer boundaries can also be formed, subject to the foregoing restrictions that all warp and weft threads must be approximately the same length and/or the multilayer fabric must be able to be pulled mostly flat and taut on the loom. Another way of understanding the limitations is that neither warp nor weft threads can reverse direction as they cross a flattened swath. For example, the tubular structure shown in FIG. 6 cannot be woven so that it inflates to the circular shape with a vertical dividing wall shown at left. The lateral seam allowances 610 and 620 and upper and lower surfaces 630 and 640 can be woven, but when the fabric is pulled taut between the selvedges as shown at right, the vertical wall 650 becomes slack and tangled, 655. However, many interior partitions can be woven in place, as shown in 660 (interior partitions 670). These interior partitions may be useful to help control the outer profile of the structure, or to provide shear and torsion resistance to the finished spar.

FIGS. 7A and 7B show how vertical inter-cell walls can be formed. To make the structure indicated generally at 700 in FIG. 7A (with cells separated by vertical walls 710, 720, 730 and 740 between lateral edges/seam allowances 750 and 760), the fabric may be woven with the edges pulled horizontally so that the cells are rhombuses rather than squares (as shown in FIG. 7B). (During weaving, the fabric is pulled virtually flat from edge to edge—the rhombi are very oblique.) When the cells are inflated, they assume a shape more like FIG. 7A (although it is appreciated that outer cell walls will still be somewhat convex, and edges will be rounded).

More generally, a complex internal structure can be manufactured by the methods of an embodiment if a cross-section through the desired structure can be pulled flat from edge to edge so that no section of weft fiber doubles back on itself.

Embodiments of the invention rely on the precise and economical manufacturing of woven-pocket structures like those described above to construct strong inflatable objects having complex shapes and (optionally) internal structures, which are also lightweight and easy to pack into smaller volumes when deflated. The following sections describe several specific applications of the inventive woven objects, including details which may be applicable or beneficial in other situations as well.

Inflatable Mattress

A simple rectangular, multiple-chamber inflatable mattress can be woven in one operation by following the pattern of FIG. 8. (Here, varying dashed-line patterns indicate locations where different subsets of the warp and weft threads are woven together. Thus, they mark places where, in traditional sewn construction, seams joining two separate pieces of fabric would be placed. However, the “seams” of an embodiment are much stronger than traditional construction because the warp and weft threads themselves are woven together—no needle-and-thread sewingor welding technology are used.

Once the desired multi-chamber article has been woven and cut from the bulk fabric, a valve is attached in a suitable location and the mattress is complete. A mattress constructed in this way may provide the desired firmness and cushioning when inflated to about 8-45 psi (of course, the firmness can be adjusted by changing the inflation pressure). At pressures in this range, a traditional valve similar to those used on pneumatic tires offers adequate performance at a reasonable cost. Also, ordinary polyester or nylon threads have adequate tensile strength to withstand the applied stresses. Threads may be coated with a thermoplastic polyurethane (“TPU”), polyvinyl chloride (“PVC”), silicone, latex, urethane or another substance, which may be heat-sealed after weaving to create an airtight inflatable structure, even if the thread count (threads per inch) and/or other characteristics of the weave would ordinarily be insufficiently dense to be airtight. Coatings such as these may also improve the fabric's structural characteristics, by (for example) reducing or eliminating bias stretch.

In an alternate embodiment shown in FIG. 9, the mattress may be woven with porous internal partitions to control the outer shape of the mattress, using the principles discussed in connection with FIG. 6.

Stand-Up Paddleboard

A second example application is an inflatable watercraft known as a stand-up paddleboard. As shown in FIG. 10, this is similar in shape and size to a traditional surfboard, but it is intended to be used by a rider standing on the upper surface and paddling/steering with a long single- or double-bladed oar. FIG. 11 shows a plan view of the paddleboard, with several possible chamber arrangements shown in cross sections at 1110-1140. The curved outline of the plan view and the curved inflatable-chamber stringers can be formed in a single weaving operation.

Like the inflatable mattress described above, the stand-up paddleboard will be inflated through a valve. However, higher internal pressure may be necessary to achieve adequate stiffness for this application. Thus, stronger threads (e.g., aramid fibers such as Kevlar®, Spectra® or Dyneema®) may be needed. Also, a higher-pressure valve may be required.

The mattress and paddleboard embodiments discussed above are woven “square” to a loom direction (i.e., with their centerline aligned with either warp or weft threads). However, complex bending and twisting characteristics of a woven structural member can be obtained by placing the centerline of the member at an angle to warp and weft threads. Such placement may be described as “on the bias,” signifying the diagonal placement. And, of course, curved spars (discussed below) necessarily have at least some portions which are not squarely aligned with warp or weft threads.

Furniture

FIG. 12 shows an inflatable couch that can be manufactured in a small number of woven sections according to the principles explained here. The large white areas 1210, 1220 and 1230 indicate inflatable channels where the fabric is woven as at least two separate outer layers (top and bottom). The cross-hatched areas 1240, 1250 and 1260 are single-thickness “seam allowance” fabric where the sections can be cut apart and then sewn together using conventional needle-and-thread techniques to create an inflatable sofa. The white area at 1270 with circles indicates a partially-inflatable area. The circles indicate places where top and bottom surfaces are woven together; these will appear as dimples in the inflated surface. The assembled couch is shown at 1280. (Note that only one of 1210 and 1220 is required to assemble the couch shown. Two components are shown nested together in this figure to illustrate that separate, independent inflatable structures may be woven together in a single loom operation to improve efficiency and reduce material waste.

FIG. 13 shows a chair 1310 constructed as a plurality of angular, three-sided inflatable tubes 1320 supporting and laced together by textile straps or elastic bands which form the seating surface. The inflatable tubes 1320 are woven as described here, and the textile bands or elastic straps may be attached to seam allowances of the tubes by sewing or by passing through grommets (e.g. at 1330-1360) fixed into the seam allowances.

Structural Members

The foregoing examples have been limited to woven and coated structures needing nothing more than simple assembly and an inflation valve to be complete. However, strong, lightweight inflatable objects according to an embodiment can also be incorporated into larger structures with other materials and elements. These embodiments will be described under the general name “spar,” which is specifically defined to mean “a structure similar to a stick or pole, having a length, a possibly-varying diameter or profile along its length, and optionally a curvature; which is subjected to compression, tension, torsion and/or bending.”

A spar according to an embodiment is an inflatable tube, often curved, woven in a single loom operation where the warp threads are oriented generally in a first direction along the tube, and the weft threads are oriented generally in a second direction across the tube. (“Along” and “across” may be interchanged if the spar is short enough to be woven across the loom, rather than along it.)

The spar is characterized in that it includes a first section where all of the adjacent warp and weft threads are woven together to form a first peripheral border of the spar; a second adjoining section where a first subset of warp and weft threads are woven together to form one outer surface, and a second subset of warp and weft threads are woven together to form a second, separate outer surface; and a third adjoining section where all of the warp and weft threads are woven together again to form another peripheral border of the spar. The first and third sections are equivalent to the “seam allowances” described earlier. If the spar is deflated and pulled flat, a swatch cut out of the second section will yield two separate and disconnected pieces of cloth, corresponding to the first and second subsets of warp and weft threads.

The spar may include a third subset of warp and weft threads woven together in the second adjoining section, which forms an interior partition or wall within the second adjoining section. In this case, the swatch cut from the second section may yield three or more separate and disconnected pieces of cloth.

Tent Support

An embodiment of the invention may be used to support a temporary structure such as a tent (FIGS. 14 & 15). Spars may be formed with two inflatable channels joined by a seam allowance (e.g. 1440), or the seam allowances of two separate spars may be sewn together. Tent-support spars (FIG. 15) can support or suspend lighter-weight tent wall material (1530).

Portable Baby Crib

An embodiment of the invention may be used to support a crib or playpen (FIGS. 16A and 16B). A lightweight mesh 1630 may be sewn or reversibly attached to the support structure by hook-and-loop fastener, zippers or other mechanisms.

Kite Surfing Wing

An embodiment of the invention may be used to form the leading edge and struts for a kite-surfing kite. The finished structure (FIG. 18) has spar segments extending in several different directions, but it can be constructed from a plurality of parts woven flat on a length of fabric according to an embodiment (FIG. 17, 1710-1740). The irregularly-shaped subsections (featuring inflatable pockets that are woven, not sewn) may be cut from the bulk fabric in the seam allowances and sewn together permanently, or reversibly connected via conventional fasteners such as hook-and-loop fabric patches. As shown in FIG. 18, the spar structure according to an embodiment is attached to wing surface skins 1850 and 1860 (preferably a lighter-weight, air-resistant fabric such as ripstop nylon), and supports those surfaces in the desired aerodynamic shape. The kite wing would be connected to a rider's harness and control handles via a bridle system (not shown).

Inflation Bladders

As noted earlier, some textile structural members according to an embodiment may be woven with a thread count (threads per inch) or thread composition that is not airtight or leak-proof. For example, the fabric may have the appearance of a gauze, where openings between adjacent warp and weft threads are clearly visible and incapable of holding air. Such woven objects may nevertheless be inflated to pressures sufficient to support structural loads by treating the threads with a thermoplastic coating that can be sealed by heat activation, or by inserting an airtight bladder into the woven pockets. In the latter arrangement, the woven structure provides support for the bladder, allowing it to contain high-pressure gas without rupturing. Note that the threads of such a “gauze” embodiment are loaded primarily in tension when inflated, even if the spar is loaded in another mode. High-tensile-strength threads are widely available and well characterized, and many are suitable for use on Jacquard looms with little or no modification. Thus, for example, a strong, high-pressure spar according to an embodiment may be constructed of an aramid-fiber gauze shell surrounding and supporting a thin rubber, silicone or polyurethane bladder that contains the inflation gas or liquid.

The present invention has been described largely by reference to specific examples and in terms of particular applications of the inventive principles. However, those of skill in the art will recognize that Jacquard-woven fabrics having complex shapes and internal structures can provide aesthetic and structural benefits to a variety of other useful articles of manufacture. Such articles are understood to be captured as embodiments of the invention if they meet the limitations of the following claims. 

We claim:
 1. An inflatable spar, comprising: a curved textile tube having warp fibers generally oriented in a first direction along the tube; and having weft fibers generally oriented in a second, different direction across the tube, wherein an adjacent plurality of weft fibers are woven together through all of a first section of warp fibers, then two subsets of the plurality of weft fibers are woven together through different subsets of a second section of warp fibers, then all of the adjacent plurality of weft fibers are woven together through all of a third section of warp fibers, the first and third sections of warp fibers thus forming a seam allowance at opposite sides of the curved textile tube and the different subsets of the second section of warp fibers forming upper and lower surfaces of the curved textile tube.
 2. The inflatable spar of claim 1, further comprising: an inflation valve installed through one of the upper surface of the curved textile tube or the lower surface of the curved textile tube.
 3. The inflatable spar of claim 1 wherein a portion of a centerline of the spar is curved relative to both the warp fibers and the weft fibers.
 4. The inflatable spar of claim 1 wherein a first portion of a centerline of the spar is parallel to the warp fibers and a second portion of the centerline of the spar is parallel to the weft fibers.
 5. The inflatable spar of claim 1 wherein a third subset of the plurality of weft fibers are woven together with a third subset of warp fibers in the second section, said third subsets thus forming an interior partition wall.
 6. The inflatable spar of claim 5 wherein the interior partition wall is airtight.
 7. The inflatable spar of claim 5 wherein the interior partition wall is porous.
 8. A woven textile comprising: a plurality of warp fibers oriented generally lengthwise along the woven textile; a plurality of weft fibers oriented generally widthwise across the woven textile, wherein a first section across a width of the woven textile includes a first selvage-like portion where all weft fibers are woven together with all warp fibers; a second portion adjoining the first portion includes a first subset of weft fibers woven together with a first subset of warp fibers and a second, distinct subset of weft fibers woven together with a second, distinct subset of warp fibers; and a second selvage-like portion adjoining the second portion where all weft fibers are woven together with all warp fibers.
 9. The woven textile of claim 8, wherein: the second portion adjoining the first portion has a third, distinct subset of weft fibers woven together with a third, distinct subset of warp fibers.
 10. The woven textile of claim 8, wherein a sample cut through a full thickness of the woven textile within second portion yields at least three separate woven swatches.
 11. The woven textile of claim 8, said second portion forming an inflatable chamber.
 12. The woven textile of claim 8, said second portion forming a plurality of adjacent inflatable chambers, at least two of such adjacent inflatable chambers sharing at least a portion of a chamber boundary.
 13. The woven textile of claim 8 wherein at least some warp fibers and at least some weft fibers are treated with a coating that can be activated to reduce porosity of the woven textile.
 14. The woven textile of claim 13 wherein the coating is a thermoplastic coating, and wherein activating is heat treating.
 15. An inflatable structure, comprising: a plurality of separate, inflatable textile components, each component cut from a length of woven fabric having shaped pockets woven therein, said components cut apart in seam allowances surrounding the shaped pockets, said plurality of separate, inflatable textile components fastened together between portions of their respective seam allowances.
 16. The inflatable structure of claim 15 wherein the separate, inflatable textile components are fastened together by sewing or welding.
 17. The inflatable structure of claim 15 wherein the separate, inflatable textile components are fastened together by lacing.
 18. The inflatable structure of claim 15 wherein the separate, inflatable textile components are fastened together to form one of a sofa or a chair.
 19. The inflatable structure of claim 15, further comprising: a textile surface fastened to a seam allowance of one of the inflatable textile components.
 20. The inflatable structure of claim 19, further comprising a bridle and harness, said structure forming a kite-surfing wing. 